Y is for Young
by sapphire blue-ruby red roses
Summary: Derek had digressed to when he was a teenager, and now the others have to figure out a way to return him to normal, but what are they willing to give up to accomplish that? two-shot for everyone's liking, rating for slight language
1. Part 1

**I know a shit ton of people are probably doing fics like this, but… I just couldn't resist. So here's mine to add to the bundle. I didn't know what age Derek has digressed to in the show, so I just made him fifteen.**

**Disclaimer: I do not own Teen Wolf**

Y is for Young

"Dude, your girlfriends are totally hot," young Derek told Stiles, his short, skinny frame sprawled out across Stiles' bed, inviting and innocent and trusting. "How did a nerd like you get **two** beautiful girls, let alone only **one** of them?" He watched Stiles with those infuriatingly blue –or maybe they were green? Maybe they were both?- eyes as he surfed the internet in a futile search for explanations and solutions.

Stiles released an irritated sigh, turning to glare at the teen that was shorter and younger than him now. "Slow down there, dude. One, I only have one girlfriend. Her name is Malia. Two, those women are two of my pack mates and best friends you're talking about. Three, they are also **your** pack mates, so show some respect. Four, **I'm** one of your pack mates, and since you can't remember shit right now, I'm revoking your privilege to insult me. Five, this-" he gestured around at the paper covered walls and colored strings connecting them, "-is to help your furry ass, so don't be a sourwolf. I have spent many a sleepless nights trying to decipher your location and now, how to get you back to normal. We've all been working our asses off trying to get you back. So don't. Be. A. Little. Shit." He emphasized each word, glaring at the fifteen-year-old.

With his point made, he swung back towards his laptop.

Derek bolted into a sitting position, staring guiltily down at his clenched fingers. "I'm sorry," he muttered. After a long moment filled with only mouse clicks, he spoke. "I still don't understand… any of this. According to you and that Scott kid, I'm a younger version of myself, at least the me that you all know. Scott is the alpha. His pack… your pack… **our** pack, is made up of two humans, a kitsune, a were-coyote, a banshee and only two werewolves. How is that possible? And then there's this thing you're telling me about my family and Kate. That she's a were-jaguar now and that she burned my entire family alive. She'd never do something like that. I know her."

Groaning, Stiles tried to remind himself that this was baby Derek, pre-Kate-Argent-is-an-evil-bitch Derek, pre-my-whole-family-burned-to-death Derek. The Derek who still trusted and loved all too willingly.

"The only thing I do know," Derek said, slowing his mouth so that it no longer rivaled Stiles', "Is that I was literally just having a laugh with my family and you were hiding behind Sheriff Stilinski's pants while my mother talked to him."

Silence befell them again. A terrible plan crossed Stiles' mind and before he could talk himself out of it, he stood, gathering his keys. It was a bad idea that was bound to go horribly wrong, but this was undoubtedly the only way baby Derek would understand. "Come on," he said, not waiting for Derek as he tramped down the stairs.

Derek scrambled after him, tugging on his shoes, following quickly after Stiles. "Where are we going?"

"Where everything started."

…..

"What… what is this? Is this some kind of joke?" Derek whispered shakily, horror spiking through him as he stood in the shadow of the husk of his family home. His eyes were wide, disbelieving.

Stiles stood back, his hands shoved deep into his pockets. Guilt trickled through his veins, poisoning his conviction and roiling his morals. "What's left after Kate's madness. I'm sorry, Derek, but that woman isn't who you think she is. And this, this is my reality, this is the reality of the older you." He was quiet, silently watching as Derek stumbled toward the house.

He fell through the gaping hole that served as the door, the house swallowing him, welcoming him like an old friend. Silence enveloped the house. Not even a cricket chirped in the tense night.

Suddenly, a howl, mournful and filled with agony, broke the silence, snapping Stiles from his unusual stillness. He jumped up the porch steps, rushing into the house. He found Derek curled in on himself on the family room carpet, face buried in his knees.

Without a second thought, Stiles wrapped himself around Derek, creating as many points of contact as he possibly could between them. He soothed a hand between Derek's shoulder blades, whispering quietly to the boy.

"Why?" Derek sobbed, wrapping his arms around Stiles chest, burying his face in the crook of Stiles' throat, "First Paige and now my family! Why does everyone close to me get hurt?"

'_We're still trying to find that answer_,' Stiles thought solemnly, tucking the boys head beneath his chin, holding him close as he remembered all the others.

…..

"…a sacrifice," Deaton's words jerked Stiles from his lack-of-sleep, comforting-baby-Derek induced stupor. He blinked through blurry eyes, staring at the man across from him. "Wait, what? Replay. Did I just hear something about a sacrifice? We all know how well that worked out for Scott, Allison and me last time. I'd rather not have a repeat of thinking I'm going crazy."

Scott watched him with eyebrows drawn close together. He'd been doing that since Stiles had walked in. Malia especially had been scowling at him. Lydia and Danny though seemed to keep shooting him knowing glanced. What they knew, he wasn't sure. Derek had forgone the invitation of the pack meeting, rather instead choosing to stay curled in Stiles' bed and never leave again. Kira was babysitting said sulking teen.

Deaton gave Stiles a curious look. "I was saying, Stiles, that to return Derek to normal, either the pack or the person closest to him has to sacrifice something they hold precious to them."

"But everybody close to him is dead," Stiles interjected, "And what could the pack possible give up?"

"Our unity," Scott murmured, staring at the steal table beneath his fingers.

Simply, Malia said, "Our humanity," crossing her arms over her middle.

"Our bond," Lydia said.

"Our strength," Danny muttered, staring out the small window, arms crossed over his chest.

Biting his lip, Stiles stared at his reflection in the table. "Is there a ritual that has to be performed?"

Deaton nodded. "There can be, but it seems the spell works best when it is done without planning or the person realizing they've done it. When it is given without thought, completely willingly."

Stiles threw his hands up, letting them flop to his sides. "Is there any other way, any at all?"

Deaton nodded again. "Yes. You can attempt to awaken the memories he doesn't remember. I suppose there are other methods that I don't have knowledge of at this point. They are less painful, but much harder to complete."

The pack was silent for a long moment. Finally, Scott said, "Let's come back tomorrow. We'll figure out what to do then." As the pack scattered, Scott caught Stiles' arm. "Hey, you've been acting weird. Did something happen with Derek? You smell of him and… grief, not yours though." He stared at his best friend imploringly, willing him to tell him what had happened.

And he almost did. Almost. "Hey, dude, we're fine. I just made a stupid mistake and now we're paying for it. Derek believes us though, so that's good news. Don't worry, everything is fine." Even as he said those words, patting Scott's bicep, he knew Scott nor any of the others especially believed him. A soothing hand passed down his spine. He knew it belonged to Lydia without having to look. "Really, everything is fine. I've got to get home before he breaks something Kira won't be able to fix."

Slipping from Scott's grasp, he was out the door before anyone else could stop him. He had just reached his Jeep when Malia pinned him against the driver side door.

"Why do you smell like that boy? I don't like it," she growled in his ear, rubbing her scent over him, covering Derek's, but not erasing it.

"He's staying at my place, remember, because I was the only one he vaguely recognized?" he replied lamely, taking her scenting without reaction. When she pressed her mouth to his, he allowed her to kiss him. After a moment though, he pushed her away. "Malia, I'm not in the mood today… I don't feel good. I'll talk to you later, alright." Pressing a short kiss to her lips, he clambered into his Jeep and took off, leaving her irritated and alone.

…..

"Mother!" Derek bolted upright, the cry on his lips, his muscles tensed and shaking, "Mother!"

The cry brought Stiles back from the brink of his own night terror, his skin slicked with sweat, heart racing beneath his breastbone. His mouth felt cotton dry as he sat forward, pulling a terrified Derek into his arms. "It was only a dream. You're awake now," he soothed as the boy clutched at his night shirt.

Since the house, the Stilinski household had become very nocturnally vocal. Stiles wasn't the only one having night terrors anymore. Since that night, Derek had taken to sleeping in Stiles' bed, seeking the touch of a pack mate from a pack he felt apart of even though he couldn't remember it. Even if he had to sneak into Stiles' room, Stiles would wake to a warm body pressed against his each morning. And despite his father's attempt to help, Stiles was the only one who could calm the teen.

He wished the change had never happened.

…..

"Ew," Derek muttered as Stiles fell face first into the bed beside him, his backpack and shoes discarded at the door.

"What are you saying 'ew' to, you little brat?" Stiles shot at the boy, glaring from his pillow, "And what is that face for?"

Derek's nose was crinkled, his eyebrows smashed together in something bordering on disgust. "You smell like that girl. I don't like it."

Rolling his eyes, Stiles propped his face in his hand. "Yes, well, she is my girlfriend after all. She says the same to me about you at least once a day. She keeps scent marking me because of you." He sighed, laughing. "You're like two dogs pissing on a tree. They never learn to share the tree."

Setting his book aside and lying with his back pressed on top of Stiles, he wiggled around like a fox in grass, spreading his scent. "Well, I don't want to share the tree," he quipped childishly, burrowing beneath Stiles.

"Neither does she," Stiles sighed, allowing himself to be manhandled.

"You know, technically, we are both does, just slightly different breeds." Derek pushed Stiles onto his back, straddling his hips and lying with his chest pressed flat against Stiles'. He nuzzled Stiles' neck for a prolonged moment before frowning in distaste. "No matter what I do, her scent always stays. Where…" His vision honed in on Stiles' lips like a predator on prey, and suddenly his mouth was covering Stiles'.

Their kiss was sloppy and full of uncontrollable giggles and spoke of inexperience. There was no saying how long it lasted, long enough for Stiles to run his fingers into Derek's hair and Malia's scent to be completely wiped from him.

Derek sighed in contentment as he pulled away, pressing his nose back into Stiles' neck. "Much better."

'_What am I doing_?' Stiles thought as he listened to Derek drift to sleep.

…..

Stiles stumbled, his body weighing heavy on Derek's smaller frame. He hadn't been hurt, but all of his strength had disappeared as they'd run from the bloody scene, draining away with the adrenaline. The pair was splattered with blood, neither of it theirs.

"Come on, Stiles, we're almost there," Derek whispered in a gasp, dragging Stiles forward inch by aching inch. They slammed into Stiles' Jeep. Derek only took a moment to load Stiles into the car before they were off.

The attack had been spontaneous, unannounced even as the man had descended on the pair of them. Derek could feel his muscles shivering and aching from the struggle, from the wolfsbane and the human sedative the man had pumped into the air. The wolfsbane had done him in almost as badly as the sedative was now working on Stiles. He could still feel the jerk of the man's body as Stiles had torn him away from Derek. The man had been human, that much Derek had figured out, a rogue hunter from Araya's group. If he hadn't been, they'd have been the ones to be the bloody scene.

Once they were finally home, cleaned and relatively safe, Derek blurted out, anger in his voice, "You shouldn't have done that! He could have killed you!"

"If I hadn't done it, he would have killed you. I couldn't let that happen. The pack would never have forgiven me, and I would never have forgiven myself," Stile murmured, sitting on the edge of the bed beside Derek.

"But you killed someone, Stiles! You should have done that! Not for me! Not when you could have died!"

"I did it to save you!" Stiles snapped, glaring at the teen, "I'm not going to say I'm sorry. I'd do it again if I had to."

Derek glared right back at Stiles, his eyes shiny with angry tears. "You could have died," he hissed before dropping his eyes, "I can't lose you. I can't lose another part of my family."

Sighing, regret slicing into him, Stiles pressed his hand over Derek's. "You're not going to lose me. I'm not going anywhere. I'll still be right here."

"Prove it," Derek demanded, lifting his eyes to stare at Stiles. They flashed that icy blue.

Taken aback, all Stiles could reply with was a choked, "What?"

Leaning over him, Derek growled, "Prove. It." Grabbing his face, Derek pressed close, surrendering himself to Stiles inexperienced hands.

…..

"Stiles. Stiles, wake up," Derek murmured, his voice deep and sounding like his normal self. He shook Stiles just the slightest. "Stiles, wake up."

Slowly, Stiles pulled himself from his peaceful sleep, groggy with bliss. "Derek, what is it? Go back to sleep," he grumbled, kissing his shoulder before finally blinking the sleep from his eyes. He was staring up into the aged face of Derek, the one that had become part of the pack through trial and error. His heart fell.

Derek was staring down at him quizzically, or more, staring at his lips in bewilderment. "Stiles, why am I in your bed naked?" he asked, "Where are my clothes?"

His eyes feeling hot, his throat thick, Stiles whispered, "You don't remember, do you?"

Derek's face fell. "Remember what?"

But Stiles didn't have the nerve to answer. He buried his face in his pillow, rumbling, "There are clothes you can wear in the top drawer. You should go tell Scott that your back to normal, he'll want to know. He can explain things to you. I don't want you here. Leave."

Taken aback by Stiles' sudden passive hostility, Derek asked, "Stiles, what happened?" leaning over the boy who now smelled of sorrow and something akin to regret.

"Just… go," Stiles repeated. He listened as Derek dressed. When the front door had clicked shut, he tried to release the sob that was stuck in his throat, curling in on himself, but it wouldn't come.

Deaton had been right. He had sacrificed something precious and he'd never get it back.

**What do you guys think Stiles gave up? I'll leave that one for y'all to try and figure out. I know what I think it is, but it changes every time I reread this. The second one-shot will probably be up in the next few days.**


	2. Part 2

**Here's the second part, hope it's to your liking. I'm not even going to pretend like I tried all that hard to edit this.**

**Disclaimer: I do not own Teen Wolf**

Y is for Young Part 2

"Stiles?" A light tap echoed into his room even as the door was slowly pushed open to admit one red-headed girl, her lips pursed. Her eyes took in the room quickly, the papers ripped from the walls and torn to shreds on the floor, the strings hanging limply against the walls after being cut in half, the distinct stench of despair and sorrow hanging in the air. Stiles' specific brand smelled sharp and almost antiseptic. Or maybe that was the nearly OCD cleanliness of the rest of the room. It reminded her of Scott after Allison's death.

A nest of blankets stirred on the bed, only a tuft of brunette hair sticking out from beneath the bundle. "Go away," came Stiles' muffled command, sharper than Lydia had been expecting, clear and sober.

"You should know by now that you can't chase me away that easily," Lydia replied coolly, quietly closing the door behind her with a soft click. She chose a spot close to where she figured his head was, curling her toes beneath her as she carded her fingers through his hair. "We're all worried about you, you know?"

"Don't be," he grunted back, but pressed into her fingers.

Lydia let the silence hang in the air until Stiles began shifting restlessly beneath his blankets before speaking. He immediately froze at her words. "What happened between you and the younger Derek? I know that's what this is about." When he remained silent, she sighed and continued. "Everyone's worried. They said you wouldn't let anyone in, not even Scott or Malia. Your dad said you've hardly eaten in three weeks, that you haven't left you room or talked to him. Malia is pissed beyond belief. She said she can't stand to be anywhere near you, not after scenting your room." She paused, but she still received no reaction. "Scott is nearly in hysterics because you won't tell him what's wrong, but he can feel how deep the sadness has cut into you, that he can't help you. I'd have to say that Derek has been the worst though."

Stiles shifted beneath the covers, closer to her, as if he was curling his body around her.

"He's been jittery and depressed ever since he turned up at Scott's back to normal. At first, he couldn't remember a thing of when he was de-aged, but he started to remember things. Little things at first and then suddenly something so large that the entire dynamic of the pack has changed. He hasn't told us what the memory is, but he thinks he's done something terrible to you, something we can't fix."

Silence. Stiles shuffled under his protections, snaking out a reaching hand, searching for hers. She threaded their fingers together, still stroking his hair with her other.

"Stiles," she whispered, "What did you sacrifice?"

A sob flitted up to her ears and suddenly, Stiles was crawling into her lap, wrapping his arms around her waist, staining her dress with wetness. "I can't do it, Lydia! I can't- he- I-" He swallowed passed his tears. "I've washed my bedding and my clothing so many times they've gotten holes in them. I've bleached my room. I've scrubbed my skin raw. But I can still smell him. His scent doesn't go away," he cried desperately, clutching at her for all he was worth, "I can't face him knowing he doesn't remember, knowing he doesn't feel the same."

He curled his body around hers, pressing his knees into her hip. "I can't face him, I can't face Malia. Neither of them will ever forgive me. I shouldn't have done it, but I did and I can't take it back and… I just… I can't face them."

Lydia could imagine what had happened between the young Derek and Stiles. She wasn't one for empathy, but her heart lurched for her friend and pack mate, especially knowing years of confidential information from the boy about himself. Hugging him close, she whispered, "You should go see him. Maybe everything will work out for the better."

He nodded, but they both knew he didn't believe her words.

…..

When Lydia called it was both to his surprise and not very surprising at all. She'd been quietly working behind the scenes, gathering information and putting everything together piece by piece for weeks. So when she finally contacted him, he'd known it was coming. The surprise had been her words, a simple, "We're coming over. Have food," and then the dial tone.

Venturing into his kitchen, he'd puzzled over who she'd possibly be bringing. His mind snatched for the obvious answer, sighing, '_Stiles_,' but he denied it, instead figuring it was probably Scott or Danny or maybe even Kira that she was bringing. Never mind Malia, the were-coyote wouldn't even occupy the same room as him during pack meetings.

"Derek, we're here!" Lydia called, bursting through the door like she pretended she wasn't, "I hope you have food because I've got an anorexic boy here." She whispered quietly to her partner in crime as the door slammed shut so that he couldn't make out a word she said. She whirled into the kitchen smelling strongly of disinfectant and grief, narrowing her eyes.

Rolling his eyes, he pulled open his fridge. "I have some leftover apple pie and roast beef that Scott's mom gave me if that's what you mean."

Lydia flashed her pearly whites. "Perfect, just the thing. Bring that out once you've done something with it for the three of us." And she was gone again to whisper to her companion.

Sighing, helpless to refuse her, Derek pulled together sandwiches and three slices of warmed apple pie, carrying the plates out to the coffee table. He set them down, not looking at Lydia's companion, before the scent finally slammed into him, Stiles scent almost completely obscured by the antiseptic smell.

Slowly raising his eyes, he realized that the grief was rolling off Stiles in waves, and now that he was paying attention, he could tell that it was specific to him. Lowering his eyes before he could catch the other's eyes, he sat across from Lydia, studying Stiles from beneath lowered lashes.

Saying that Stiles looked terrible was an understatement. Dark smudges marred the skin beneath his usually bright hazel eyes. His eyes were red-rimmed and blood-shot. His already pale skin was more pale than usual, as if he hadn't opened his curtains or turned on a light in a week and a half. He was skinnier than before, the bones of his face sticking out more sharply. His usual nervous energy had turned to that of anxiety, throwing tremors through his hands and legs every few moments.

This was Derek's fault. He had done this to Stiles.

"Eat," Lydia commanded with more softness than usual, pushing the plate towards him, "It's Mrs. McCall's cooking."

"Please," Derek murmured in an almost inaudible whisper.

As Stiles finally pulled a place towards him, Lydia began to speak, "I don't know what happened between the two of you, but I can guess, and what I'm guessing has broken rulers' power and gotten people killed. I **know** that it has changed our pack dynamic and it needs to be fixed. Now." They fell silent, Lydia's eyes skipping expectantly between the pair.

"I'm sorry," Derek finally muttered, staring down at his clasped fingers between his knee, "We should never have-"

Stiles cut him off, voice harsh and on the breaking point, "Don't say it. Don't you dare say that, Derek Hale. What was the point of all of it if you say something like that?"

"Stiles, you're underage. I should know better," Derek said imploringly, his mind wincing as he thought back to the way Kate Argent had used him.

"So were you at the time!" Stiles exploded, glaring at him across the small table.

"That's not the point. The point is that you're underage and I knew that I'm older than you," Derek rebuked, staring back just as harshly, "I'm grateful to you for getting me back to normal, but it should never have happened!" Derek flinched back as the tears came spilling down Stiles' cheeks.

Lydia stared up at him with wide, surprised eyes.

"You asshole, you fucking asshole, you were what I sacrificed my innocence for or whatever the fuck I sacrificed? I gave you so many things. How is that fair? How does that make sense? I killed for you. I gave you more than one type of innocence," Stiles snarled, throwing his words like daggers as he scrubbed at his face, "You have the memory, but do you really remember it? You weren't fucking using me, you didn't even know that was going to turn you back and neither did I. You weren't the only one who made that decision. Do you really remember? Look me in the eyes and tell me you do."

Derek didn't have to say a word as he looked up into those hazel eyes, not that he could have spoken anyway. He did remember. He remembered every second from when he'd woken in the tomb to when he'd drifted to sleep that last night. He remembered every word spoken that night. He remembered every laugh, every kiss, every caress, every flash of heat that had flooded his young body. He remembered the fall. He was sure he hadn't found the ground yet, and that scared him more than anything.

"Tell me again that it should have never happened," Stiles whispered.

Derek couldn't, not to his face, not when he knew Stiles could see right through him to his very core. He felt fifteen again in the moment. Dropping his eyes, the only think he could whisper was, "I can't be like Kate."

"If you were anything like Kate, do you really think I'd be here right now?"

…..

Bounding into Scott's living room, the acting pack headquarters, Stiles threw himself at Lydia, wrapping her in a crushing bear hug. "I finally got it back!" he whispered to her excitedly.

"Got what back?" she asked, even though she already knew that answer, grinning into his chest.

Stiles cut his eyes to Derek where he was accepting more leftovers and a slice of cake from Mrs. McCall. He couldn't help but remember the 'birthday present' he'd received in the early hours of that morning. "Ssh, I can't say. It's precious and just might slip away again."

Pulling away, Lydia grinned a true smile. "Deaton never said that you couldn't get it back over and over again." Smoothing down his sleeves, she tried not to follow Malia's movements behind him. "So, how are those scratches?"

Glancing over his shoulder, Stiles smiled wanly. The whole thing with Derek hadn't gone over well with his ex-girlfriend. Even after months, she was still likely to attack one of them on random. He still had scratches from the most recent attack last week during the full moon. "Ah, they still sting. They weren't that deep though. I think Derek got the worst of it."

Patting him on the shoulder, Lydia said, "I'm sure it'll work out for the best," before moving to talk to Danny about his new hard drive.

**I hope that didn't suck as much as I felt it did. I liked writing the first part, and I liked writing Lydia trying to help, but I don't know. How did you guys like it?**


End file.
